Vicious PQI. huh. Shouldn't that be out of the pool, for the same reasons we dont get PQI with the vicious badge?

No. The way I understand it, Vicious dungeons are supposed to spawn in PQI, but they get a hidden completion bonus so won't spawn until you've completed most of the non-Vicious dungeons to a sufficient degree.

(It's pretty clear that the PQI hasn't worked as intended since it was implemented, but that part seems to have worked well enough)

Well in case anyone's looking to add the info to the wiki - it kicked off when above 75% everywhere. Also, when you get high enough, the redundancy levels go really screwy in general. Either that or I'm looking for completion and it keeps prioritising my rare race/class combo's over "what you played where", so more runs end up being redundant completion wise than not.

Also, I don't mind vicious PQI kicking in at 75% (you're hardly a newbie if you have that much, that a lot of runs). However, if it's prioritizing stuff you haven't played elsewhere it's sending you up a creek without a paddle. Miser Transmuter Gnome took me a big bunch of tries, and I'm not exactly inexperienced. And I only had a gnome wizard run in there, so it could've picked anything at all.

The PQI picks the lowest percent dungeon with vicious getting a 50% bonus. So if everything is 75 and vicious is less than or equal to 25 then you'll get sent there. If the PQI there is too hard, get up above 25% and do the burning to get a different PQI quest.